1. Field of the Invention
This invention relates to surgical positioning devices, and more particularly to an adjustable surgical frame to support and stabilize a patient to facilitate spinal surgery.
2. Description of the Related Art
During orthopedic surgery, when the lumbar spine is to be operated on, the patient must be placed in a position which takes pressure off the chest cavity and the abdomen. One commonly used position is the modified knee-chest position where the knees of the patient are not actually positioned against the chest but rather are bent to a right angle with the hips similarly bent to a right angle. A special positioning device is required to maintain a patient in this modified knee-chest position.
One such device was developed by Michelson, U.S. Pat. No. 4,481,943 ('943) issued on Nov. 13, 1984. The '943 patent discloses a surgical frame for use during surgery to position a patient in the modified knee-chest position and reduce the tension on the neural structures during surgery. While the surgical frame of the '943 patent had its advantages, certain short comings became known during its use.
One problem experienced during the use of the '943 frame was that the patient was positioned relatively high with respect to a surgeon of average height. When the '943 frame was placed on an operating table, it sat relatively high on the operating table requiring the surgeon and his assistants to stand on a raised platform or other supporting surface during surgery in order to access the spine of the patient. This set up was relatively dangerous because the surgeon or the assistants could fall from the platform and injure themselves or the patient during the operation. Moreover, the '943 frame could not be adjusted to position the patient in an adequate lowered position to facilitate access to the lumbar spine for a surgeon of average height, especially for taller patients.
Another problem encountered with the '943 frame was that the '943 frame was too bulky and heavy which created problems in storing and transporting the frame. Although the '943 frame had legs with a roller mechanism, the roller mechanism would become impeded by the normal dust and wax present on the operating room floor and would prevent the '943 frame from being rolled so that it had to be carried. Yet another problem encountered by the '943 frame was that it was not attachable to the various types of operating tables used in surgery because it was not adaptable to fit the differing side rail dimensions and inter-rail widths of the various operating tables used in spinal surgery.
A further problem with the '943 frame was that the top portion of its side frame members extended above the level of the patient's spine and would interfere with the area near the wound of the patient, so that during surgery, the surgeon would have to work around the top portion of the side frame members. The top portion of the side frame members would also prevent the use of the '943 frame with peripheral surgical equipment such as an instrument stand, which is normally placed adjacent to the wound site so that a flat working surface adjacent to the wound and level with the height of the spine of the patient is created.